Sleeping or???

[The_silliest]

I have two hermit crabs and one molting currently and the other was fine until one day I couldn't find him for a day or two, the I found the other one half buried with his shell sticking out, and he wasn't moving, now the tank is starting to smell and I don't know the exact reason.
I'm worried because I don't know if they both are now molting or dead and I'm really worried

[Wai]

So is one crab completely missing and not in the tank anymore? For the crab hanging out of its shell, is there an abdomen attached to the body?

[The_silliest]

I found him in the tank under a piece of decor like he was trying to bury himself, but I could still see most of his shell and he wasn't moving for a few days. So I don't know if he's trying to molt or if something's wrong.

[Wai]

If he isn’t hanging loose from his shell, you can leave him there as is.